Tank thermometer



F. E. BROWN 2,663,191 TANK THERMOMETER Filed Nov. 1s, 1948 Dec. 22, 1953 :A An

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Patented Dec. 22, 1953 UNITED sTATEs raTENT OFFICE TANK THERMOMETER Frank E. Brown, Burbank, Calif., assignor to 'l Frederick M. Turnbull, LosvAngeles, Calif.

Application November 13.1948, seria'iN'o. 59,862

My invention relates to improvements in thermometers and more particularly to thermometers adapted to be utilized to ascertain the temperature of the contents of large tanks, such as storage tanks, at various levels therein.

For the purpose of illustrating the manner of construction and mode of operation of my invention, it is described as being utilized in conjunction with a storage tank containing volatile fluids such as gasoline, but it is obvious that my invention may be utilized in a wide variety of applications and I, therefore, do not intend to limit its use to the specific eld herein discussed.

It is common practice in the oil industry to take the temperature of the contents of storage tanks at different levels within the tanks to assertain the temperatures of said contents at said different levels in order that the volume of the liquid contents may be accurately calculated on a standard temperature base. To make these temperature readings, a tubular thermometer of conventional typeis inserted into the interior of the tank through an opening in the top thereof and is permitted to descend in the contents of the tank to a predetermined level. The thermometer is held at the predetermined level until its temperature rises to the temperature existing at said level, and it is then drawn upwardly through the body of the fluid to the exterior of the tank for reading. Since the temperature of the liquid above the level at which the temperature reading has been made is frequently several degrees above the temperature at the reading level and since the vaporsat the top of the tank are also at a higher temperature, it frequently happens that thethermometer, when drawn to the exterior of the tank, shows a temperature which is greater than the temperature of the predetermined level at which it was suspended. Naturally, the inaccurate temperature reading results in inaccurate gaging of the contents of the storage tank..

It is, therefore, a primary object of my invention to provide a thermometer adapted to ascertain the temperature of the contents of a storage tank ata predetermined level thereof which will not be influenced by the temperatures of the liquid above the predeterminedlevel or by the temperature of the vapors above said liquid.

Other factors tending to render temperature readings obtained with an ordinary thermometer inaccurate are the exposure of the thermometer to atmospheric temperatures at the exterior of the tank and the volatilization of the iluids retained upon the surface of the thermometer which induces a refrigeration effect and materially lowers the temperature reading.`

A, a 9 claims. (1173+340) f" l Y Another object of my invention is the provision of a thermometer which will not beimmediately affected by its exposure to atmospheric temperatures or the volatilizati-on of fluid upon its surface.

An additional object of my invention is the provision of a tank thermometer which includes a conventional tubular thermometer mounted within a housing having a transparent wall portion through which the indicia upon thebody of the thermometer tube can be read.

Frequently, the indicia upon conventional thermometers utilized for the purpose indicated are so small that the reading thereof is diiiicult and occasionally results in the recording of erroneous temperature gures.

It is a further object of my invention to provide a tank thermometer which includes a housing having a transparentwall portion adapted to magnify, to some extent, the indicia upon the surface of a thermometer tube enclosed within said housing.

It is a concomitant object of my invention to provide a tank thermometer which includes a housing having a transparent, intermediate portion enclosing' a thermometer tube, said portion incorporating a body of iuid adapted to isolate and separate the thermometer tube from the wall of the intermediate portion in order to stabilize a temperature reading obtained upon the thermometer `tube by insulating the thermometer tube temporarily from'the fluid levels through which the tube is drawn after a reading has been made at a predetermined level. v

An additional object of my invention is th provision of a tank thermometer embodying a thermometer tube surrounded by a body of fluid adapted to insulate the thermometer tube temporarily from surrounding fluid or atmosphere, in which the thermometer tube has its vertical axis eccentrically positioned with respect to the vertical axis 'of said housing to place the greater proportion of the body of fluid in front of said tube to magnify the indicia borne upon the tube.

Since tank thermometers are frequently subjected to rough usage, it is desirable to protect them as effectively as possible against the results of rough handling. Another object of my invention is the provision of a housing incorporating a conventional thermometer tube which provides Y shock-absorption means adapted to isolate said tube from impact blows borne upon said housing. Of course, the uid in which the thermometer tube is immersed also serves to cushion any shocks which may be borne by said housing.

An additional object of my invention is the provision of an apparatus for taking the temperature oi fluids stored within a tank which includes a guide means adapted to be inserted into the contents of the tank and designed to receive a thermometer therein, said guide means serving to prevent the deflection of said thermometer within the contents of said tanl; andalso toprevent damage to said thermometer;

An additional object of my invention is the provision or" a thermometer having a transparent, intermediate portion which is shielded from injurious contact with surrounding areas byhurnpn` ers provided at the opposite endsof. said. inter.- mediate portion.

Another object of my invention is the provision of a tank thermometer'including'ahousing having an intermediate transparent portionyvhich. is provided with a transparent plastic coating adapted to seal the joints in said housing against the leakage of iluid from the* interior' of: said housing or the seepage of fluid' from the exterior thereof into said interior.

An additional obiect'o my invention is the provision oi a tank thermometer having a smooth surface from which the fluid in which it has been immersed can be readily removed in order that an indicia reading can he readily made.

Other objects and advantages of my invention will be made apparent by a consultation ofi the following specification and the accompanying drawing, in which: n

Fig. l is a vertical, p'artly'sectional, partly'elevational view showing an apparatus constructed in accordance with my'invention and'installedin a storage tanlr;

Fig. 2 is an enlarged elevational the broken line 3 2 of Figl;

Fig. 3 is a fragmentary, vertical, sectionaly view of a thermometer' constructed in accordance with my invention;

Fig. fi is a transverse, sectional view" taken. on broken lined-i of Fig. 3;

Fig. 5 is a longitudinal, sectional view showing a preferred. form of 'sealing means utilized inconjunction' with niy temperature-gagingapparatus; and

Fig. 6 is a graph indicating the manner in view taken on 'which athermorneter constructed in accordance with my invention will retain a specicl temperature reading for a predetermined time.

Referring to the drawing, I show an oil storage tank Ic, having' a circular side' wall il. provided with a top or roof l2 and bottone; The roof i2 is shown as being a conventional movable or floating roof which is. adapted to move up and down within the circular wall li ofY the tank` as the quantity of iluid within the tanl: increases, or decreases. Gf course, my invention isnot limited to use with a tank of any particular construction, since it is obvious that it can loe as. readily used with a tank having a iixed roof' or top or noY roof. Stairs i5 are provided which.. permit. they ga'ger tainingl the temperature reading to mount. to a platform le which overhangs the roo'r l2 ofthe tank I0.

Projecting upwardly through the movable roof l2 or the tank lil, adjacent the platform i6, is the upper end iii of a guide means in the iorrnv of a pipe I9, the greater portieriV of Whose length is disposed within the interior of the tank il) and liquid 2l contained therein. The lower end 20 of the guide pipe lil rests upon the bottom I3 of the tank lll and may be securely attached thereto to prevent lateral movement of the guide pipe I9 when the liquid 2l is being removed from or fed into the tank l0.

i the immediate tubular portion El oi the housi Provided along the length oi the guide pipe i9 is a plurality or vertically spaced slots or longitudinal openings 22. These slots or openings 2E are oppositely disposed, as is shown in Fig. 2 of the drawing, and permit the Iluid stored within the tank lil to iow through the interior or' the, guide pipev it, for a purpose which will be describedV in greater detail below. Since the fluid 2i stored Within the tank i@ is commonly y azvolatile hydrocarbon, such as gasoline, vapors,

indicated generally at 2t, tend to rise to the spaoebetween the surface of the liquid 2i and the roof. i2 of` thetanir..

lt isV welll known that Vthe temperature at diin ferent levels within a large volume of liquid such as-gasoline-will"vary considerably and, therefore, areading taken at one level of such a .body of fluid' does not necessarily indicate the temperature of the remainder ci the fluid at different levels. Thus, the openings are provided in the length of the guide iii adjacent predetermined levels ii/'ithin the cody of fluid 2l stored in the tanl; l@ so that an accurate reading of the temperature at the diiierent levels of the huid 2l may be secured. For instance, one ci the openings VZ-'i is disposed within the fluid zone A and another of the openings 22 is disposed within the fluid zone 1%. Thus, fluid in these zones is able to circulate through the oppositely dis posed openings and into the interior of the guide pipe itl, for a purpose which will be described in greater detail below.

A string of connected tanl: thermometers is adeuztedV to he' immersed in the cody oi fluid 2i and to be guided thereinto and maintained therein hy means oi the guide pipe iii. Each ci the tank 'thermometers 25 includes an elongated housingv 26 comprising' an intermediate transn parent tubular portion 2l, which provides a transparent wallv 2%, and enlarged end in the form of plugs The intermediate tuhu lar portion 27, in the present'ernhodinient'oi'rny invention, constitutes greater length ci the housing Zt, but it is, of course, oovious that length of the tubular portion will he determined ley the temperature range in which the thfr:i morneter 25 is designed to operate. The ends of 26 are'closed by means o the plugs ha* f. cylindrical, reduced portions pted inserted into the ends oi the intermediate tu bular portion il and to be `fastened therein means' of a suitable adhesive to isolate the' in teriorA oi the intermediate tubular portion 2l from contact the fluid il in which the thermometer 25 is to be immersed. Although. any material having transparent qualities may be utilized to iorin the intermediate tubular portion 2l of the thermometer I prefer to use a plastic substance which, while providing the necessary transparency, is also sucstanti lly unhrealz.- able and possessed of suiiicient flexibility to permit` the. intermediate, tubular portion 2l to bend slightly when. the housing 25 strikes upon an adjacent objeet. lit is also contemplated that the portion 2 may loe inade of a 'tempered such as Pyrex. The curvilinear wall 2% is also utilized to provide a magnifying cit-feet for an object housed within the intermediate tubular portion, as will be described in greater detail oelow.

The plugs which serve to close the opposite ends of the intermediate tubular portion 2l have integral, expanded portions it which serve as bumper means to prevent the exterior of the wall 28 from contacting adjacent surfaces and being of Ythe drawing, when one of the thermometers is suspended within the interior of the guide pipe I9, it is desirable that it be suspended with its vertical axis substantially co-axial with the vertical axis of said guide pipe I9. Since any abrasion of the exterior of the transparent wall 28 would result in reducing the transparency of said wall, the bumper portions 33 of the plugs 30 prevent the contact of said wall 28 with the interior of the guide pipe I9. In addition, when the thermometers are suspended within the interior of guide pipe I9, they are disposed within said interior adjacent the vertical slots or openings 22 so that the fluid 2| within the diiferent zones may flow through the openings about the periphery of the housing 26. The bumper portions 33 of the plugs 50 serve to prevent the wall 28 of Vthe intermediate tubular portion 21 of the housing 26 from engaging the openings 22 in a sealing relationship therewith and which would prevent the free flow of the iluid through the openings 22 and about the periphery of the housing 26 ofthe f thermometer 25.

Secured in the plugs 30, as by being molded therein, are eyes 35 having elongated shafts 35 upon the ends of which are formed integraldiscs 31 surrounded with the material, preferably plastic, of which the plugs are formed and which serve to prevent the dislodgment of the eyes 35 from the bodies of the plugs 30. Y When the intermediate tubular portion 21 is made of tempered glass, the plugs 3B may also be molded in glass. The utilization of the eyes '35 instead of the conventional bails previously utilized in tank thermometers prevents the inadvertent loss of the housing 26 and thus avoids the possibility that a thermometer 25 may be left within the guide pipe i 9.

When it is desired to ascertain the temperature of the fluid 2| at different levels within the storage tank I0, a plurality of the thermometers 25 is strung together by means of the eyes 35 and strong, flexible cords 38 which are knotted to the eyes at opposite ends of the thermometers. The cords' are of suiiicient length to juxtapose the thermometers 25 to the openings 22 in the guide pipe I9 when the entire string of thermometers has been let down into the guide pipe I9.

Secured to the upper end of the string of thermometers 25 and connected thereto by means of one of the cords 38 is a ball 39 which is adapted to rest upon the top of the guide pipe i9 when the thermometer string is let down into the interior of said pipe. In addition to functioning as a grasping means by which the thermometer string may be let down into and withdrawn from the interior of the tank I0, the ball 39 serves as a clossure to seal the opening to the interior of the tank IG through the body of the guide pipe I9 and thus prevents the loss of vapors contained within the tank I@ through the guide pipe I9.

The space defined by the wall 28 of the intermediate tubular portion 21 of the housing 26 and closed off by the plugs 39 constitutes a generally cylindrical chamber 40 which serves as a receptacle for a body of liquid 4| which is adapted to be permanently retained within the chamber 40. An expansion space 42 is provided within the chamber 40 to accommodate the expansion of the liquid 4|. The liquid utilized, in the present instance, is glycerin, but Ido not intend to limit my invention to any specific liquid since a wide variety of liquids may be satisfactorily utilized for the purpose of my invention.

6 Disposed within the chamber 40 is a glass thermometer tube 45 of conventional design, having a central bore 46 which terminates at the lower end of the thermometer tube in a bulb 41 in which -is conventionally stored a supply of mercury 48 or similar medium adapted to respond to temperature changes in the liquid in which the thermometer tube 45 is positioned. `Spaced indicia 50 are engraved or otherwise formed in the periphery of the tube 45 and serve to indicate the Vtemperatureof the fluid Zone in which the thermometer has been immersed. The thermometer tube 45 is mounted within the chamber 40, as best seen from Fig. 4 of the drawing, with its vertical axis positioned to one side of, i. e. eccentrically -to, the vertical axis of the chamber 40 and the Y housing 2B.

` By thus positioning the thermometer tube 45 eccentrically with respect to the vertical axis of the housing 26, the greater amount of the liquid 4| is interposed between that portion of the thermometer which bears the indicia and the wall 28. In this manner, the magnifying effect secured lby the convexity of the wall 28 is substantially enhanced by the magnifying effect of the body of the liquid 4I disposed before the indicia 5t withinthe chamber 40. Although the greater proportion of the liquid 4| is disposed before the portion Vof the thermometer tube 45 bearing the indicia 55, it should be observed that, at no time, is the thermometer tube 45 in contact with the adjacent wall 2S'since the liquid 4|, in addition to performing a magnifying function, serves also to thermally insulate the thermometer tube from the Wall 28.

Provided in the reduced portions 3| of the plugs 30 are seats 52 which are adapted to receive .the oppositely disposed ends of the thermometer tube 45 and to locate the thermometer tube 45 in a predetermined orientation with respect to the vertical axis of the housing 25 thereof. Disposed within the seats 52 in contact with the opposite ends of the thermometer tube 45 are shockvabsorption means 54 constituted by coil springs 55. When the housing Z6 of the thermometer 25 strikes upon an object, the vertical components of force are absorbed in the shock-absorption means 54, and loads which might otherwise fracture the thermometer tube 45 are rendered harmless. By providing the shock-absorption means 54 and the body of liquid 4| surrounding the thermometer tube 45, the possibility of damage to the thermometer tube 45 by shock load is practically eliminated, and the life of the thermometer tube is greatly prolonged.

' Since it is desirable that, when the thermometer string isinserted in the top I3 of the guide pipe I9, the entire string be carried downwardly through the pipe I9 to the bottom 20 thereof, the lowermost thermometer 45 is Weighted so that its weight Will draw-the thermometer string downwardly inthe guide pipe I5. For this purpose,

lthe lower plug 3|! is provided with an elongated .cylindrical opening 51 which is adapted to receive :a cylindrical, lead plug 58 and the base of the Vopening is closed by a plug 59 which is connected thereto. Y

When the thermometer housing 25 is completely assembled, the assembly is dipped in a transparent plastic substance which provides a smooth coating Si! of plastic which lls the various joints in the housing 26 and prevents the leakage of uid thereinto and the leakage of liquid therefrom. In addition to preventing fluid leakage, the plastic coating 60 serves to presenta smooth exterior to tener.

G .the body of the fluid 2l in which .it is immersed.

Therefore, when the thermometer lit is Withrawn from the top iii of the guide pipe it, the iluid accumulated upon the surface thereof can ce readily wiped o the plastic coating e@ so that the thermometer indicia 5S may be immediately read before any possibility that a temperature change can induce a change in the thermometer reading.

Since the upper end i8 oi the guide pipe I9 projects through the movable roof I2 of the tank it, it is necessary that the roof i2 be sealed in respect to the periphery of the guide pipe i9 and sealing means adaptedto seal the opening 6I in the roof l2, as best shown in Fig. 5, isprovided to prevent the leakage of volatile fumes through the opening 5i in the roof i2. The Vportion of the root i2 surrounding the opening is provided with an annular downstruck flange b2, adjacent which is mounted a circular, iiexible gland (i4, which may be formed of rubber or similar material, adapted to Wipe upon the periphery of the guide pipe iii. The outer edge of the gland ring t4 is secured against the means of a ring t5, formed of metal, and having an upstruck annular flange t5. The ring 65 is secured to the top of the roof i2 by means of bolts 61 and nuts or any other desirable fas- ,.is the roof i2 rises and falls with the change in the amount oi fluid stored Within the tank it, the inner edge of the gland ring E4 is carried along the periphery' of the tube i9 in sealing relationship therewith. Thus, the leakage of fumes or fluids through the opening 6| in the roor lil is prevented.

The graph shown in Fig. 6 indicates, on line C, the temperature drop which is encountered in the use of conventional tank thermometers, While line D indicates the thermometric inertia oi a thermometer constructed in accordance with my invention. While a time lag of one minute is shown by the graph, in most applications the time lag is for a substantially longer period and can, ci course, be controlled by changing the dimensions of the housing and the spacing o1 the thermometer tube with respect to the wall thereof.

Thus, I provide by my invention a tank theracometer having an intermediate tubular portion which is defined by a transparent Wall enclosing a chamber adapted to contain a body of liquid. immersed in the body ci liquid is a thermometer tube which is positioned eccentrically with respect tc the vertical axis of said chamber. The indicia drawn upon the thermometer tube are magnified by the body of liquid contained in the chamber and the thermometer tube is insulated from the surrounding atmosphere and surrounding fluid by the body of liquid. In addition, the body or" liquid serves to retain the indicia upon the thermometer tube in a state of initial clarity and absorbs a proportion of the shock loads imposed upon the housing oi the thermometer. The thermometer is provided With shock-absorption means adapted to prevent the fracture of the thermometer by vertical loads imposed upon the housing thereof. Bumper means are provided at opposite ends of the housing adapted to prevent abrasive contact of the transparent Wall of the housingwith surrounding areas and the entire housing is enclosed in a plastic sheath adapted to permit the ready removal of liquid accumulated thereupon to permit the immediate reading of the thermometer. Also, a guide pipe is employed which extends downwardlyA into the top of the roof l2 by interior of a `storage tank and is provided with oppositely disposed openings adapted to permit fluid contained in the tank to now therethrough into contact with the periphery of the thermometer tocommunicate the temperature of the fluid to said thermometer.

In operation, when one of the thermometers 25 is immersed in the :duid 2 I Within the storage tankn lo, the fluid-flows through the openings 22 of the guide pipe i9 into contact with the walls of the thermometers At rst, the contact or the fluid 2! with the thermometers 225 serves only to affect the liquid lil Within the chambers liti, but eventually the heat of the fluid Within the storage tank iii is communicated through the liquid il to the thermometer tubes i. When the thermometers 25 .are drawn upwardly through the adjacent levels of fluid, which may be at diierent temperatures, the thermoinetric inertia afforded to the tubes t5 by the insulation eiect of the liquid 4i prevents the temperatures recorded upon the thermometer tubes of the thermometers 25 from being altered as they pass upwardly throng liquid sones having different temperatures and through the vapors 23 at the top of the interior of the tank It. Y

In addition, when each thermometer 25 is Withdrawn from the top i8 or the guide pipe i9 and exposed to atmospheric temperatures and to the evaporation of the iuid upon the surface of the housing 2t, the insulating characteristics of the liquid il in the chamber it Will prevent such iactors from having an immediate effect upon the temperature recorded by the thermometer tube t5.

Thus, the liquid it! contained Within the chamber il of the housing 2:3 of each thermometer 25 serves to partially absorb any shock loads borne upon the housing 2t of the thermometer 225 and to isolate the thermometer tube s therefrom, to magnify the indicia iid upon the surface of the thermometer tube t5 and to impart a thermometric inertia or stability to the thermometer tube t5, which permits the thermometer tube It to maintain a temperature reading recorded thereupon although exposed to variant conditions which Would tend to change said reading. The fact that the body of the thermometer tube lib is continually suspended in the liquid ti serves to maintain the indicia it upon the thermometer tube i5 in a condition of initial clarity so that no difficulty is ever encountered in reading said indicia.

Although I have shown and described a preferred embodiment of my invention for the purlpose of illustrating its form of construction and manner of operation, it is obvious that changes, substitutionsand modifications may be made in the specific elements of the invention shown and I, therefore, do not intend to be limited to said specinc elements but desire, rather, to be afforded the full scope of the patent claims.

T. claim as my invention:

l. In a thermometer adapted to be wholly irnmersed in a body of fluid, the combination of: a housing, said housing including an intermedie Je tubular portion having a transparent wall and dening a chamber in which is permanently contained a body of liquid; and a bulb thermometer ltube having indicia formed thereupon entirely disposed within said chamber and having at least its bulb portion and the greater portion of its length bearing said indicia completely surrounded by said body of liquid.

2. A combination as defined in claim l, in

which said tube has its longitudinal axis eccentrically positioned with respect to the longitudinal axis of said chamber.

3. A combination as dened in claim 1, in which said chamber has positioned in opposite ends thereof shock-absorption means and said shock-absorption means and said tube are eccentrically positioned with respect to the longitudinal axis of said chamber.

4. In a thermometer adapted to be wholly immersed in ay body of iluid, the combination of: an elongated housing including an intermediate tubular portion having a transparent wall and delining a cylindrical chamber; a body of liquid permanently contained in said chamber; and a separate thermometer tube entirely disposed -in said chamber having indicia formed thereupon and having the lower portion of its length and the major portion of said indicia immersed in and surrounded by said liquid.

5. A combination as dened in claim 4, in which said housing includes bumper means, said bumper' means providing seats for the opposite ends of said tube, said seats iand said tube being eccentrically disposed in relation to the vertical axis of said housing.

6. A combination as dened in claim 4, in which said housing includes bumper means and one of said bumper means is provided with weight means adapted to cause said thermometer to be carried downwardly through said body of iiuid.

'7. In an apparatus adapted to ascertain the temperature of the contents of a deep tank, the combination of: fa plurality of elongated thermometers attached to one another and spaced a predetermined distance apart, each of said thermometers including a housing having an intermediate tubular portion provided with a transparent wall, the tubular portion dening a chamber in which is permanently located a body of insulating liquid and a bulb thermometer provided with indicia entirely disposed within said chamber and having at least its bulb portion and the greater length of the portion bearing said indicia completely surrounded by said body of liquid; `and a guide pipe vertically positioned within said tank and protruding from the top thereof, said guide pipe having a plurality of verl0 tically spaced openings formed therein, adjacent which said thermometers are adapted to be positioned, the said openings permitting the contents of said tank to circulate past said thermometers.

8. An apparatus as defined in claim 7, in which the external diameter of a portion of said thermometers is substantially less than the internal diameter of said guide pipe to permit said contents to circulate through said openings in said guide pipe about said portion.

9. A housing for a tubular thermometer having indicia formed upon the surface thereof including: an intermediate portion having a transparent Wall deiining a chamber for receiving said thermometer, said housing providing upper and lower seats for receiving the opposite ends of said thermometer, and the longitudinal axes of said seats being eccentrically disposed with respect to the longitudinal axis of said housing; and a body of liquid contained in said chamber, the greater portion of said liquid lying in front of said indicia when said thermometer is disposed in said seats.

FRANK E. BROWN.

References Cited in the ille of this patent UNITED STATES PATENTS Number Name Date 577,016 Fairchild Feb. 16, 1897 1,561,659 Nichols Nov. 17, 1925 1,868,911 Phelps July 26, 1932 2,104,218 Betzold et al Jan. 4, 1938 2,316,677 Edwards et al Apr. 13, 1943 FOREIGN PATENTS Number Country Date 24,435 Germany Apr. l1, 1883 7,150 Great Britain Feb. 10, 1894 (1893) 25,361 Great Britain Nov. 2, 1895 1894) 26,321 Sweden May 15, 1907 OTHER REFERENCES Ingersoll (Article) Physics. vol. 2; March 1932 (pages and 156 relied on). 

